hewitt



S OF INTERNAL COMBUSTION ENGINES.

Patented Dec. 2, 1919.

E. R. HEWITT 0N IN THE MANIFOLD PPLlcATloN man FEB.

3 num/Lto@ aal'd Sito/Mam MEANS T0 MEASURE THE SUCTI ATENT FlffllE-.

EDWARD n. HEWITT, oii iviiDvALE, NEW JERSEY.

MEANS TO MEASURE THE SUCTION IN THE MANIFOLDS F IN TERNAL--COMBUSTION ENGINES.

Maasai.

Specification of Letters Patent.

Patented Dec.. 2, 19319.

Application filed February 15, 1919. Serial No. 277,251.

To all whom t may concern:

'Be it known that I, EDWARD R. HEwiTT, a citizen of the United States, residing in the to-wn of Midvale, county of Passaic, State of New Jersey, have invented certain new and useful Improvements in Means to Measure the Suction in the Manifolds of Internal-Combustion Engines, of which the following is a specification, reference being had to the accompanying drawings, illus- .trative of one particular embodiment of my invention.

My invention relates to the economical operation of internal combustion engines, and more particularly to the use of means to conserve fuel in the operation of such engines. I have discovered that the suction measured in a certain part of the intake manifold is practically an exact index of the percentage of maximum power being developed by the motor at any time. In view of this discovery I provide means to indicate to the operator of an engine the power condition, so that the operator may effect the necessary regulation of the engine for economy and thereby conservation of fuel.

In view of m discovery, one particular means of practising the conservation of fuel is shown in the accompanying drawing, in which- The perspective fragmentary View of the forward part of a motor car shows one4 manifold, D is the throttle valve lever, E is a carbureter, F is a coupling connecting the end of the suction tube G with the manifold C. H is a suction gage connected with the tube G, and mounted upon the instrument board J of the dash of the motorcar. On thel suction gage I prefer to have a guide mark indicating for the particular motor, the approximate critical suction point where economy begins and rapid increase of waste ceases; which-in practice would be a red mark at the predetermined point, 'which I.

have indicated as H on the suction gage.

It will be seen that the suction gage II connects with a. tube which leads from the manifold between the throttle operated by the throttle lever D,'and the engine A, so

etc., it is substantially true for all motors of the Otto cycle type operating on gasolene or kerosene. It willbe appreciated that on farm tractors where the power required is fairly high relatively, and also in trucks, it is most important that the motor operates economically on fuel. The usefulness of myinvention will be further evident, because the fuel consumption per horse power developed increases rapidly with the reduction of the load on the motor, as, for instance, when the load is less than 50 or 60 per cent. of maximum, the consumption of fuel will be greatly increased per horse power.

For any particular motor and carbureter, the exact suction for relative power must be exactly determined if an accurate result is required, but such accuracy is not necessary for approximate power readings. I find that in general a suction of 8 of Hg. corresponds to 50 per cent. of maximum load and that below this point the fuel economy becomes rapidly worse. In operating a tractor the operator should watch the gage, and if the suction rises above the 8 mark then he should shift his gears so as to reduce the speed and increase the load of the n. A)tor and thereby secure better fuel economy. My suction gage therefore is preferably marked with a red line oi special designation at the predetermined critical point, such as the 8 suction mark, and therefore any operator can readily be taught the meaning of the suction condition so that he will change gears and thereby operate the engine under the most advantageous conditions.

It will be evident that the conservation of fuel in the millions of internal combustion engines nowin operation, is 'a factor of the greatest economic importance, not alone at this time but a matter of great concern for the coming years. 'ihe primary object 'of gasoline or kerosene, which 1n some cases of course, where the operator may eect the has resulted in most complicated devices, smetlmes of great eXpense,-and my discovery is therefore of greatest importance as a deduction from innumerable tests which I have conducted or supervised, because it has led to the provision of very simple and economical means to effect real economy and conservation of fuel. The means for such saving may be very inexpensively attached to an existing motorsfor to any new motors and\ or motor cars, tractors, trucks,-in fact any internal combustion engine, primarily,

load conditions by a change of gear'or other like regulation.

While the benefits of my discovery may be realized in various ways, other than the means shown in the particular embodiment ,in the accompanying drawing, what I claim and desire to secure by Letters Patent 1s:

engine, a suction measuring' device located for convenient observation and the better serving as an indicator of the load factor and relative fuel econom in the motor, and a connection between sai manifold and said suction measuring device.

In testimony whereof, I have signed my name to this specification, in the presence of two subscribing witnesses, this 13th day of Feb., 1919.

EDWARD R. I-IEWITT;

Witnesses:

HERMAN F. CUN'rz, H. MUCHMORE. 

